Phonograph-tone-arm joint.



M. CLARK. PHONOGRAPH T ONE ARM JOINT.

APPLICATION FILED APR. 5. 1917. I

?&t8lltd Sfipt. 25, 191?.

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MELVILLE annex, 'or onrcneo, rumors, Assrcnon 'ro runnvrtnn other: rrnno I GGMPANY, or cnroneo, rumors, A conroaarrcn or runners.

PHONOGRAEH-TONE-ARM JOINT.

' To all whom it concern:

Be it known that I, Mnnvnmn CLAmn'a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful vide an improved bearing joint for the tone arm of a talking machine for its swinging movement over the record. It COIISIStS IH the elements and features of COIIStIllOtlOIl shown and described as indicated in the claims.

. In thedrawings:

Figure 1 is a side elevation of a portion of a phonograph comprising the tone arm and adjacent portion of the sound conduit equipped with this invention.

Fig. 2 is a detail vertical section axial with respect to the tone arm joint.

Fig. this a section at the line, 33, on Fig. 2. I

The drawings show. in a conventional manner the tone arm and sound box of a phonograph with the adjacent portion of the sound conduit and the record support and record thereon, \the invention relating solely to the portions constituting the joint for connection of the tone arm with the adjacent portion oi th'econduit for swinging the tone arm horizontally over the record for playing. The tone arm, A, terminates for said joint in a downwardly-extending elbow arm, A which has a flange, A, transverse to the vertical axis of the joint, that is, the axis about which said tone arm swings, which is the vertical axis of the adj acent fixed sound conduitmem'ber, B, upon which said tone arm 1s mounted for said swinging movement. On saidfiange there. n

a sound conduit member upon which it is are jour'naled rollers constituting two sets, the individuals of which alternate with each other about the axis of said swinging movement, the rollers, C, of one set having their axes radial with respect to the axis of said swingingmovemenh-that 1s, for rolhng in Specification of Letters Patent. Pgt gmmgqfi scr pt, 25, 391*? Application filed April 5, 1917. Serial No. 159,891.

vertical planes,and the rollers,-D, of the other set having their axes parallel to the axis of the swinging movement,that is, for rolling in horizontal planes. The said sound conduit member, B, has at its upper end an inwardly-open annular track which 1s formed most conveniently by an interiorlyrabbeted or inwardly-flanged collar, B secured upon the upper side of an outwardly turned flange, B of said sound conduit member, said annular track being positioned and proportioned to accommodate both sets of rollers, the set of rollers, D, being engaged between the upper and lower sides oi said annular track, while the rollers, D,

travel upon the back or vertical wall of said track. The second set of saidrollers, it will" be observed, serve to center the swingingtone arm co-axiallywitlg. the .ad acent menuber of the sound conduit, 3, and relieve the friction of the swinging movement which might otherwise result fromthe tendency to horizontal movement of the tone arm bodily,

whiie the first set' of rollers positions-the tone arm vertically by their engagement between the top and bottom walls of said track, and relieve the friction of said swinging movement due to the overhanging weight of the tone arm.

I claim I 1. In a talking machine,- a tone arm and a sound conduit member upon which it is supported for swinging over the record, said member having an annular track transverse to, opening toward, and encompassing the axis of said swinging movement, and the 'tone arm having at the end which engages said conduit member two sets of rollers, those of one set having their axes radial, and those of the other set having their axes parallel to said. first-mentioned axis, both sets being engaged with said annular track. 2. In a talking machine, a tone arm and supported for swinging over'the record, said member having an annular track transverse to, opening toward, and encompassing the axis oi said swinging movement, and the tone arm having at the end which engages messes said oonduii; mem'bel' two sets of rollers, the both sets being" engaged with said annulae individuals of which alternate with each track.

other in circumferential order about said In testimony whereof, I have hereunto set axis, those of one set having their axes ramy hand at Chicago, Ellinois, this 2nd day 10 5 dial, and those of the other set having their of April, 1917.

axes parallel to said first-mentioned axis, I MELVILLE CLARK. 

